Roofing structural system having dove tail joint roof decking and insulation fastening systems incorporated therein

ABSTRACT

A new and improved fastening system which is adapted for fastening a roof decking structure to an underlying truss-shaped roofing substructure, as well as for fastening roofing insulation slab members to the roof decking structure, comprises a plurality of dove tail fastening joint structures comprising, for example, a plurality of male tenon and female mortise members integrally formed or defined upon the underlying truss-shaped roofing substructure, a plurality of male tenon and female mortise members integrally formed or defined upon the roof decking structure, and a plurality of male tenon and female mortise members integrally formed or defined upon the insulation slab members. The dove tail fastening joint assemblies therefore permit the roof decking structure to be fixedly secured upon the underlying roof decking substructure, and to permit the insulation slab members to be fixedly secured upon the roof decking structure, by simply sliding the structures with respect to each other so as to form the dove tail joint assemblies.

FIELD OF THE INVENTION

The present invention relates generally to roofing structural systems, and more particularly to a new and improved roofing structural system which has a new and improved dove tail joint fastening system incorporated therein which is adapted for fastening the roof decking to the underlying roofing substructure, as well as for fastening the roofing insulation slabs to the roof decking wherein male tenon and female mortise members formed upon the underlying roofing substructure will effectively interface respectively with the female mortise and male tenon members formed upon the roof decking, and in a similar manner, the male tenon and female mortise members of the roof decking will effectively interface respectively with the female mortise and male tenon members formed upon the insulation slabs.

BACKGROUND OF THE INVENTION

Roofing structures, particularly low-slope or shallow-slope roofing structures, conventionally comprise a plurality of roofing components, such as, for example, a roofing substructure comprising, for example, a truss structure, roof decking which is adapted to be secured atop the truss structure, and slabs of insulation which are adapted to be secured atop the roof decking. Conventional installation techniques for fastening, securing, or connecting the aforenoted roofing components together comprise, for example, the use of adhesives, screw-type fasteners, nails, roofing plates, and the like, however, the use of such means for fastening, securing, or connecting the aforenoted roofing components together is quite labor intensive, costly, and time-consuming. For example, as can readily be appreciated, in view of the fact that such screw-type fasteners, roofing plates, adhesives, and the like, must be installed or secured at numerous positions located throughout the entire expanse of the roofing structure, the installation or construction process requires an inordinate amount of manual labor, the cost for the fastening members is substantial, and it obviously requires a considerable amount of time for the workmen or construction site personnel to install all the fasteners in order to complete the roof installation or construction process. Still yet further, it can be additionally appreciated that when one or more of the roofing components needs to be replaced, such replacement procedures will likewise be labor-intensive, costly, and time-consuming in view of the fact that each one of the fastening members or components must be removed and then re-installed.

A need therefore exists in the art for a new and improved fastening system for use in connection with roofing installations wherein the fastening system will be relatively simple in structure, will be quick and easy to install, and will therefore be economically viable and cost-effective.

SUMMARY OF THE INVENTION

The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved fastening system which is adapted for fastening roof decking structure to an underlying truss-shaped roofing substructure, as well as for fastening roofing insulation slab members to the roof decking structure, wherein the fastening system comprises a plurality of dove tail fastening joint structures comprising, for example, a plurality of male tenon and female mortise members integrally formed or defined upon the underlying truss-shaped roofing substructure, a plurality of male tenon and female mortise members integrally formed or defined upon the roof decking structure, and a plurality of male tenon and female mortise members integrally formed or defined upon the insulation slab members.

In this manner, the male tenon and female mortise members of the truss-shaped sub-structure are adapted to be respectively mated with the female mortise and male tenon members of the roof decking structure, and in a similar manner, the plurality of male tenon and female mortise members of the roof decking structure are adapted to be respectively mated with the female mortise and male tenon members of the insulation slab members. Once the roof decking structure is secured to the underlying truss-shaped roofing substructure by mating the male tenon and female mortise members of the roof decking structure to the female mortise and male tenon members of the underlying truss-shaped roofing substructure so as to form the dove-tail joint structures therebetween, only a single screw fastener, adhesive means, weldment, or the like is required to fixedly prevent the roof decking structure from undergoing any slidable movement with respect to the underlying truss-shaped roofing substructure. In a similar manner, once the insulation slab members are secured to the roof decking structure by mating the male tenon and female mortise members of the roof decking structure to the female mortise and male tenon members of the insulation slab members so as to form the dove-tail joint structures therebetween, only a single screw fastener, adhesive, or the like is required to fixedly prevent the insulation slab members from undergoing any slidable movement with respect to the roof decking structure. Various different embodiments of the roof decking structure and the truss-shaped roofing substructure are disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other features and attendant advantages of the present invention will be more fully appreciated from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views, and wherein:

FIG. 1 is a perspective view of a roofing structural system which has incorporated therein a first embodiment of a new and improved roofing and insulation fastening system which has been constructed in accordance with the principles and teachings of the present invention, and which shows the cooperative parts thereof wherein dove tail fastening joints are used to secure both the roof decking to the underlying roofing substructure, as well as to secure roof insulation slab members to the roof decking;

FIG. 2 is an exploded, enlarged view of the fastening system illustrated within FIG. 1 showing one of the transversely oriented rail members, a plurality of transversely spaced joists integrally attached to the upper surface portion of the rail member so as to thereby effectively form a plurality of transversely male tenon members, as well as a plurality of transversely female mortise members between the plurality of transversely spaced joists, of the dove tail joint to be defined between the underlying roofing substructure and the roof decking, the roof decking which has defined therein a plurality of male tenon and female mortise members for respectively mating with the female mortise members defined between the joist members, and the male tenon joist members, of the underlying roofing substructure, and an insulation slab member which has a plurality of male tenon and female mortise members defined therein for respectively mating with the plurality of female mortise and male tenon members defined within the roof decking so as to define the dove tail joint between the insulation slab member and the roof decking;

FIG. 3 is a view similar to that of FIG. 2 showing, however, a second embodiment of a new and improved roofing and insulation fastening system, constructed in accordance with the principles and teachings of the present invention, wherein the roof decking is adapted to be fixedly attached to the conventional rail members of the underlying roofing substructure in a conventional manner, such as, for example, by suitable welding techniques, bolt fasteners, pins, rivets, or the like, however, the roof decking is adapted to be fixedly attached to the insulation slab member by means of a dove tail joint fastening system in a manner similar to that illustrated within the embodiment of FIG. 2; and

FIG. 4 is a view similar to that of FIG. 3 showing, however, a third embodiment of a new and improved roofing and insulation fastening system, constructed in accordance with the principles and teachings of the present invention, wherein the roof decking is adapted to be fixedly attached to the underlying roofing substructure in a conventional manner, such as, for example, by suitable welding techniques, bolt fasteners, pins, rivets, or the like, while the roof decking is adapted to be fixedly attached to the insulation slab member by means of a dove tail joint fastening system in which the plurality of male tenon members of the roof decking, between which the female mortise members of the roof decking are defined, comprise solid structures for mating with female mortise members of the insulation slab member.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, and more particularly to FIGS. 1 and 2 thereof, a first embodiment of a new and improved a roofing structural system, which has incorporated therein a new and improved roofing and insulation fastening system which has been constructed in accordance with the principles and teachings of the present invention for use in connection with, and which shows the cooperative parts thereof wherein dove tail fastening joints are used to secure both the roof decking to the underlying roofing substructure, as well as to secure the roof insulation slab members to the roof decking, is disclosed and is generally indicated by the reference character 10. More particularly, it is seen that the roofing structural system 10 comprises an underlying roofing substructure 12 to which a roof decking component 14 is adapted to be fixedly attached, and an insulation slab member 16 which is adapted to be fixedly attached to the roof decking component 14. The underlying roofing substructure 12 is seen to comprise a plurality of substantially M-shaped truss members 18, only one of which is illustrated within FIG. 1, which are adapted to be spaced predetermined distances from each other along the longitudinal extent L of the roofing structural system 10, and the M-shaped truss members 18 have upper and lower transversely oriented rail members 20,22 respectively attached to the upper and lower extremities or terminal end portions thereof. In addition, a plurality of laterally or transversely spaced joist members 24 are adapted to be fixedly or integrally attached to the upper surface portion of each one of the plurality of transversely oriented upper rail members 20.

In accordance with the unique and novel structural features characteristic of the present invention, and as can best be appreciated from FIG. 2, it is seen that each one of the plurality of joist members 24 has a substantially trapezoidal cross-sectional configuration so as to effectively define a male tenon member to be used within a dove tail joint assembly or fastening system as will be described more fully shortly hereafter. In view of the fact that the plurality of joist members 24, forming the male tenon dove tail joint members, are transversely or laterally spaced from each other by means of predetermined distances, and in view of the additional fact that the joist members 24 have the aforenoted trapezoidal cross-sectional configurations, then the spaces formed between each pair of the laterally spaced joist members 24 effectively define female mortise joint components 26 which likewise have substantially trapezoidal cross-sectional configurations.

In a similar manner, it is seen that the roof decking component 14 comprises, in effect, a metal plate member which has a substantially sinusoidal or corrugated cross-sectional configuration comprising a plurality of alternating ridges and grooves, as considered in the lateral or transverse direction, however, unlike conventional roof decking components wherein the corrugations substantially follow a true sinusoidal curvature or configuration, the ridges and grooves characteristic of the roof decking component 14 of the present invention structural system 10 define male tenon and female joint components so as to respectively structurally interface in an interdigitated manner with the female mortise and male tenon joint components 26,24 defined upon the underlying roofing substructure 12 by means of the laterally or transversely spaced joist members 24 thereof. More particularly, it is seen that the metal roof decking member 14 is fabricated so as to be provided with a plurality of laterally or transversely spaced, longitudinally oriented, upwardly extending or upstanding ridge structures 28, and a plurality of laterally or transversely spaced, longitudinally oriented, downwardly extending or dependent groove structures 30, wherein each one of the upstanding ridge structures 28 and each one of the dependent groove structures 30 has a substantially trapezoidal cross-sectional configuration. The trapezoidal cross-sectional configurations and internal dimensions characteristic of the upstanding ridge structures 28 of the metal roof decking member 14 match with or correspond to the trapezoidal cross-sectional configurations and external dimensions characteristic of the joist members 24 of the underlying roofing substructure 12, and in view of the fact that the bottom wall member of each one of the trapezoid-configured upstanding ridge structures 28 of the metal roof decking member 14 has effectively been omitted, it can therefore be appreciated that each one of the upstanding ridge structures 28 of the metal roof deck member 14 forms a downwardly-opening space which effectively defines a female mortise dove tail joint member 32.

In a similar manner, the trapezoidal cross-sectional configurations and external dimensions characteristic of the dependent groove structures 30 of the metal roof decking member 14 match with or correspond to the trapezoidal cross-sectional configurations and internal dimensions characteristic of the spaces 26 defined by the upper surface portions of the rail members 20 and between adjacent pairs of the joist members 24 of the underlying roofing substructure 12, and in view of the fact that the upper wall member of each one of the trapezoid-configured spaces 26 has effectively been omitted, it can likewise be appreciated that each one of the spaces 26 forms an upwardly-opening space which effectively defines a female mortise dove tail joint member. Accordingly, when it is desired to fixedly connect the metal roof decking member 14 to the underlying roofing substructure 12, the plurality of joist members 24 of the underlying roofing substructure 12, which effectively define the male tenon dove tail joint members or components, can be slidably inserted along the longitudinal extents thereof into the downwardly-opening spaces 32 which are formed beneath and within the upstanding ridge structures 28 of the metal roof decking member 14 and which effectively define the aforenoted female mortise dove tail joint members or components.

In a similar manner, the plurality of dependent groove structures 30 of the metal roof decking member 14, which also effectively define additional male tenon dove tail joint members or components, can be slidably inserted along the longitudinal extents thereof into the upwardly-opening spaces 26 which are formed between the upper surface portions of the rail members 20 and the pairs of adjacent joist members 24 of the underlying roofing substructure 12 and which effectively define the additional aforenoted female mortise dove tail joint members or components, such that the male tenon dove tail joint members 24,30 and the female mortise dove tail joint members 26,32 together define a dove tail joint assembly whereby the metal roof decking member 14 and the underlying roofing substructure 12 are securely fastened together.

With reference continuing to be made to FIG. 2, it is further seen that a similar dove tail joint assembly is defined between the metal roof decking member 14 and the insulation slab member 16. More particularly, it is to be appreciated that the insulation slab member 16 is effectively a mirror-image of the underlying roofing substructure rail components 20 and joists 24 whereby the insulation slab member 16 will be able to be mated with and fastened to the metal roof decking member 14 in a manner which is similar to, but which is effectively the reverse of, the manner by which the underlying roofing substructure 12 has been mated with and fastened to the metal roof decking member 14. Accordingly, it is seen that the insulation slab member 16 is fabricated so as to be provided with a plurality of laterally or transversely spaced, longitudinally oriented downwardly extending or dependent ridge structures 34, and a plurality of laterally or transversely spaced, longitudinally oriented, upwardly extending groove structures 36, wherein each one of the dependent ridge structures 34 and each one of the upwardly extending groove structures 36 has a substantially trapezoidal cross-sectional configuration. The trapezoidal cross-sectional configurations and external dimensions characteristic of the dependent ridge structures 34 of the insulation slab member 16 match with or correspond to the trapezoidal cross-sectional configurations and internal dimensions characteristic of the plurality of dependent groove structures 30 of the metal roof decking member 14, and in view of the fact that the upper wall member of each one of the trapezoid-configured dependent groove structures 30 of the metal roof decking member 14 has effectively been omitted, it can be appreciated that each one of the dependent groove structures 30 of the roof decking plate member 14 effectively defines a female mortise dove tail joint member 38.

In a similar manner, the trapezoidal cross-sectional configurations and internal dimensions characteristic of the upwardly extending groove structures 36 of the insulation slab member 16 match with or correspond to the trapezoidal cross-sectional configurations and external dimensions characteristic of the upwardly extending ridge structures 28 of the metal roof decking member 14, and in view of the fact that the lower wall member of each one of the trapezoid-configured groove structures 36 of the insulation slab member 16 has effectively been omitted, it can likewise be appreciated that each one of the groove structures 36 forms a downwardly-opening space that effectively defines a female mortise dove tail joint member. Accordingly, when it is desired to fixedly connect the insulation slab member 16 to the metal roof decking member 14, the plurality of upstanding ridge structures 28 of the metal roof decking member 14, which effectively define the male tenon dove tail joint members or components, can be slidably inserted along the longitudinal extents thereof into the downwardly-opening spaces 36 which are formed within the insulation slab member 16 and which therefore effectively define the female mortise dove tail joint members or components, and in a similar manner, the plurality of dependent ridge structures 34 of the insulation slab member 16, which also effectively define additional male tenon dove tail joint members or components, can be slidably inserted along the longitudinal extents thereof into the upwardly-opening spaces 38 which are formed or defined within the groove structures 30 of the metal roof decking member 14 and which therefore effectively define additional female mortise dove tail joint members or components, such that the male tenon dove tail joint members 28,34 and the female mortise dove tail joint members 36,38 together define a dove tail joint assembly whereby the insulation slab member 16 and the metal roof decking member 14 are securely fastened together.

It is to be noted that once the metal roof decking member 14 has been mated with and secured to the underlying roofing substructure 12 by means of the aforenoted dove tail joint assembly comprising the male tenon dove tail joint members 24,30 and the female mortise dove tail joint members 26, 32, one or more fasteners 40, as illustrated within FIG. 1, may be inserted through, for example, the upstanding ridge structures 28 of the metal roof decking member 14 and into the joist members 24 of the underlying roofing substructure 12 so as to effectively prevent any relative longitudinal movement or shifting of the metal roof decking member 14 with respect to the underlying roofing substructure 12. In a similar manner, once the insulation slab member 16 has been mated with the metal roof decking member 14 by means of the aforenoted dove tail joint assembly comprising the male tenon dove tail joint members 28,34 and the female mortise dove tail joint members 36,38, one or more fasteners, not illustrated for clarity purposes, may likewise be inserted through, for example, the insulation slab member 16 and into the upstanding ridge structures 28 of the metal roof decking member 14, as well as into joist members 24 of the underlying roofing substructure 12 so as to effectively prevent any relative longitudinal movement or shifting of the insulation slab member 16 with respect to the metal roof decking member 14 and the underlying roofing substructure 12.

With reference now being made to FIG. 3, a second embodiment of a new and improved roofing and insulation fastening system, constructed in accordance with the principles and teachings of the present invention, is disclosed and is generally indicated by the reference character 110. It is to be noted that the second embodiment of the new and improved roofing and insulation fastening system 110, as disclosed within FIG. 3, is substantially similar to the first embodiment of the new and improved roofing and insulation fastening system 10 as disclosed within FIGS. 1 and 2, except as will be noted more fully hereinafter, and therefore, the description of the second embodiment of the new and improved roofing and insulation fastening system 110, as disclosed within FIG. 3, will be confined to the differences between the second embodiment of the new and improved roofing and insulation fastening system 110, as disclosed within FIG. 3, as compared to the first embodiment of the new and improved roofing and insulation fastening system 10 as disclosed within FIGS. 1 and 2. In addition, those structural components of the second embodiment of the new and improved roofing and insulation fastening system 110, as illustrated within FIG. 3, which correspond to those structural components of the first embodiment of the new and improved roofing and insulation fastening system 10 as illustrated within FIGS. 1 and 2, will be designated by similar reference characters except that they will be within the 100 series.

More particularly, it is seen that the second embodiment of the new and improved roofing and insulation fastening system 110 comprises a plurality of rail members 120 of an underlying roofing substructure, it being noted that only one of the rail members 120 is actually illustrated, a metal roof decking member 114 adapted to be fixedly fastened to the plurality of rail members 120, and an insulation slab member 116 which is adapted to be fixedly fastened to the metal roof decking member 114. In accordance with the principles and teachings of this second embodiment of the new and improved roofing and insulation fastening system 110, it is noted that, unlike the first embodiment of the new and improved roofing and insulation fastening system 10 as disclosed within FIGS. 1 and 2, the metal roof decking member 114 is adapted to be fixedly attached to the rail members 120 of the underlying roofing substructure in a conventional manner, such as, for example, by suitable welding techniques, bolt fasteners, pins, rivets, or the like, and only the metal roof decking member 114 is adapted to be fixedly attached to the insulation slab member 116 by means of a dove tail joint fastening system.

More particularly, it is seen that the metal roof decking member 114 comprises a structure which is substantially identical to the metal roof decking member 14 of the first embodiment of the insulation fastening system 10 as illustrated within FIGS. 1 and 2 and which comprises a plate or planar member wherein the undersurface planar portion 142 of the metal roof decking member 114 may be secured directly atop the upper surface portions 144 of the rail members 120 of the underlying roofing substructure in accordance with the aforenoted conventional manner, such as, for example, by suitable welding techniques, bolt fasteners, pins, rivets, or the like. In addition, in a manner similar to that characteristic of the roofing and insulation fastening system 10 illustrated within FIGS. 1 and 2, a plurality of laterally or transversely spaced, longitudinally oriented, upwardly extending or upstanding ridge structures 128 are provided upon or extend upwardly from the upper surface portion 146 of the metal roof decking member 114, and accordingly, adjacent pairs of the plurality of laterally or transversely spaced, longitudinally oriented, upwardly extending or upstanding ridge structures 128 define a plurality of laterally or transversely spaced, longitudinally oriented, downwardly extending or dependent groove structures 138 therebetween. The plurality of upstanding ridge structures 128, as well as the plurality of groove structures 138 formed therebetween all have substantially trapezoidal cross-sectional configurations.

Continuing further, it is seen that the insulation slab member 116 is fabricated in a manner similar to that characteristic of the insulation slab member 16 so as to be provided with a plurality of laterally or transversely spaced, longitudinally oriented downwardly extending or dependent ridge structures 134, and a plurality of laterally or transversely spaced, longitudinally oriented, upwardly extending groove structures 136, wherein each one of the dependent ridge structures 134 and each one of the upwardly extending groove structures 136 has a substantially trapezoidal cross-sectional configuration. The trapezoidal cross-sectional configurations and external dimensions characteristic of the dependent ridge structures 134 of the insulation slab member 116 match with or correspond to the trapezoidal cross-sectional configurations and internal dimensions characteristic of the plurality of dependent groove structures 138 formed upon the metal roof decking member 114, and in view of the fact that the upper wall member of each one of the trapezoid-configured dependent groove structures 138 of the roof decking plate member 114 has effectively been omitted, it can be appreciated that each one of the dependent groove structures 138 of the metal roof decking member 114 effectively defines a female mortise dove tail joint member.

In a similar manner, the trapezoidal cross-sectional configurations and internal dimensions characteristic of the upwardly extending groove structures 136 of the insulation slab member 116 match with or correspond to the trapezoidal cross-sectional configurations and external dimensions characteristic of the upwardly extending ridge structures 128 formed upon the metal roof decking member 114, and in view of the fact that the lower wall member of each one of the trapezoid-configured groove structures 136 of the insulation slab member 116 has effectively been omitted, it can likewise be appreciated that each one of the groove structures 136 forms a downwardly-opening space that effectively defines a female mortise dove tail joint member. Accordingly, when it is desired to fixedly connect the insulation slab member 116 to the metal roof decking member 114, the plurality of upstanding ridge structures 128 of the roof decking plate member 114, which effectively define male tenon dove tail joint members or components, can be slidably inserted along the longitudinal extents thereof into the downwardly-opening spaces 136 which are formed within the insulation slab member 116 and which therefore effectively define the female mortise dove tail joint members or components, and in a similar manner, the plurality of dependent ridge structures 134 of the insulation slab member 116, which also effectively define additional male tenon dove tail joint members or components, can be slidably inserted along the longitudinal extents thereof into the upwardly-opening groove structures 138 of the metal roof decking member 114 and which therefore effectively define additional female mortise dove tail joint members or components, such that the male tenon dove tail joint members 128,134 and the female mortise dove tail joint members 136,138 together define a dove tail joint assembly whereby the insulation slab member 116 and the roof decking plate member 114 are securely fastened together.

It is lastly noted that, in accordance with the principles and teachings of the present invention, while the plurality of longitudinally oriented, upwardly extending ridge structures and male tenon members 28,128 of the metal roof decking members 14,114 comprise hollow structures, alternatively, a third embodiment of a new and improved roofing and insulation fastening system, constructed in accordance with the principles and teachings of the present invention, and generally indicated by the reference character 210, is illustrated within FIG. 4 wherein the plurality of longitudinally oriented, upwardly extending ridge structures and male tenon members 228 of the metal roof decking member 214 can be fabricated as solid members. It is to be noted that the third embodiment of the new and improved roofing and insulation fastening system 210, as disclosed within FIG. 4, is substantially the same as that of the second embodiment of the new and improved roofing and insulation fastening system 110 as disclosed within FIG. 3, except as will be noted more fully hereinafter, and therefore, the description of the third embodiment of the new and improved roofing and insulation fastening system 210, as disclosed within FIG. 4, will be confined to the difference between the third embodiment of the new and improved roofing and insulation fastening system 210, as disclosed within FIG. 4, as compared to the second embodiment of the new and improved roofing and insulation fastening system 110 as disclosed within FIG. 3. In addition, those structural components of the third embodiment of the new and improved roofing and insulation fastening system 210, as illustrated within FIG. 4, which correspond to those structural components of the second embodiment of the new and improved roofing and insulation fastening system 110 as illustrated within FIG. 3, will be designated by similar reference characters except that they will be within the 200 series. More particularly, the only significant difference between the third embodiment of the new and improved roofing and insulation fastening system 210, as disclosed within FIG. 4, and the second embodiment of the new and improved roofing and insulation fastening system 110 as disclosed within FIG. 3, resides in the fact that the plurality of upstanding ridge structures 228 formed upon the upper surface portion 246 of the metal roof decking member 214 comprise solid structures as opposed to the plurality of substantially hollow upstanding ridge structures 128 formed upon the upper surface portion 146 of the metal roof decking member 114.

Thus, it may be seen that in accordance with the principles and teachings of the present invention, there has been provided a new and improved fastening system which is adapted for fastening a roof decking structure to an underlying truss-shaped roofing substructure, as well as for fastening roofing insulation slab members to the roof decking structure, wherein the fastening system comprises a plurality of dove tail fastening joint structures comprising, for example, a plurality of male tenon and female mortise members integrally formed or defined upon the underlying truss-shaped roofing substructure, a plurality of male tenon and female mortise members integrally formed or defined upon the roof decking structure, and a plurality of male tenon and female mortise members integrally formed or defined upon the insulation slab members. The dove tail fastening joint assemblies therefore permit the roof decking structure to be simply fixedly secured upon the underlying roof decking substructure, and to permit the insulation slab members to be simply fixedly secured upon the roof decking structure, by effectively sliding the structures with respect to each other so as to form the dove tail joint assemblies in a quick, easy, and cost-effective manner.

Obviously, many variations and modifications of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein. 

1. A system for fastening a roof decking member onto an underlying roofing substructure, comprising: a roofing substructure; a roof decking member; first male fastening members, and first female fastening members, formed upon said roofing substructure; and second female fastening members, and second male fastening members, formed upon said roof decking member for respectively cooperating in a fastening manner with respect to said first male fastening members, and said first female fastening members, formed upon said roofing substructure so as to fixedly secure said roof decking member onto said roofing substructure.
 2. The system as set forth in claim 1, wherein: said first male fastening members formed upon said roofing substructure, and said second female fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said roof decking member onto said roofing substructure; and said first female fastening members formed upon said roofing substructure, and said second male fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said roof decking member onto said roofing substructure.
 3. The system as set forth in claim 2, wherein: said first male fastening members formed upon said roofing substructure, and said second female fastening members formed upon said roof decking member, as well as said first female fastening members formed upon said roofing substructure, and said second male fastening members formed upon said roof decking member, have substantially trapezoidal geometrical configurations.
 4. The system as set forth in claim 2, wherein: said first male fastening members formed upon said roofing substructure, and said second male fastening members formed upon said roof decking member comprise dove tail tenon joint members; and said first female fastening members formed upon said roofing substructure, and said second female fastening members formed upon said roof decking member comprise dove tail mortise joint members, whereby said male tenon and female mortise dove tail joint members together form a dove tail fastening joint.
 5. The system as set forth in claim 1, wherein: said first male fastening members formed upon said roofing substructure comprise a plurality of transversely spaced, upwardly projecting joist members; said first female fastening members formed upon said roofing substructure comprise spaces defined between adjacent pairs of said plurality of transversely spaced, upwardly projecting joist members of said roofing substructure; said second male fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented downwardly projecting groove members for interfacing in an interdigitated manner with said spaces defined between said adjacent pairs of said plurality of transversely spaced, upwardly projecting joist members of said roofing substructure; and said second female fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented upwardly projecting ridge members for interfacing in an interdigitated manner with said plurality of transversely spaced, longitudinally oriented, upwardly projecting joist members of said roofing substructure.
 6. A system for fastening an insulation slab onto an underlying roof decking member, comprising: an insulation slab; a roof decking member; first male fastening members, and first female fastening members, formed upon said insulation slab; and second female fastening members, and second male fastening members, formed upon said roof decking member for respectively cooperating in a fastening manner with respect to said first male fastening members, and said first female fastening members, formed upon said insulation slab so as to fixedly secure said insulation slab onto said roof decking member.
 7. The system as set forth in claim 6, wherein: said first male fastening members formed upon said insulation slab, and said second female fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said insulation slab onto said roof decking member; and said first female fastening members formed upon said insulation slab, and said second male fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said insulation slab onto said roof decking member.
 8. The system as set forth in claim 7, wherein: said first male fastening members formed upon said insulation slab, and said second female fastening members formed upon said roof decking member, as well as said first female fastening members formed upon said insulation slab, and said second male fastening members formed upon said roof decking member, have substantially trapezoidal geometrical configurations.
 9. The system as set forth in claim 7, wherein: said first male fastening members formed upon said insulation slab, and said second male fastening members formed upon said roof decking member comprise dove tail tenon joint members; and said first female fastening members formed upon said insulation slab, and said second female fastening members formed upon said roof decking member comprise dove tail mortise joint members, whereby said male tenon and female mortise dove tail joint members together form a dove tail fastening joint.
 10. The system as set forth in claim 6, wherein: said first male fastening members formed upon said insulation slab comprise a plurality of transversely spaced, longitudinally oriented, downwardly projecting ridge members; said first female fastening members formed upon said insulation slab comprise upwardly extending spaces defined between adjacent pairs of said plurality of transversely spaced, longitudinally oriented, downwardly projecting ridge members of said insulation slab; said second male fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented upwardly projecting ridge members for interfacing in an interdigitated manner with said spaces defined between said adjacent pairs of said plurality of transversely spaced, longitudinally oriented downwardly projecting ridge members of said insulation slab; and said second female fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented upwardly projecting groove members for interfacing in an interdigitated manner with said plurality of transversely spaced, longitudinally oriented, downwardly projecting ridge members of said insulation slab.
 11. The system as set forth in claim 6, wherein: said roof decking member comprises a planar member; and said second male fastening members formed upon said roof decking planar member comprise substantially hollow ridge structures.
 12. The system as set forth in claim 6, wherein: said roof decking member comprises a planar member; and said second male fastening members formed upon said roof decking planar member comprise solid ridge structures.
 13. A system for fastening a roof decking member onto an underlying roofing substructure, and for fastening an insulation slab onto the roof decking member, comprising: a roofing substructure; a roof decking member; an insulation slab; first male fastening members, and first female fastening members, formed upon said roofing substructure; second female fastening members, and second male fastening members, formed upon said roof decking member for respectively cooperating in a fastening manner with respect to said first male fastening members, and said first female fastening members, formed upon said roofing substructure so as to fixedly secure said roof decking member onto said roofing substructure; and third female fastening members, and third male fastening members, formed upon said insulation slab for respectively cooperating in a fastening manner with respect to said second male fastening members, and said second female fastening members, formed upon said roof decking member so as to fixedly secure said insulation slab onto said roof decking member.
 14. The system as set forth in claim 13, wherein: said first male fastening members formed upon said roofing substructure, and said second female fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said roof decking member onto said roofing substructure; and said first female fastening members formed upon said roofing substructure, and said second male fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said roof decking member onto said roofing substructure.
 15. The system as set forth in claim 13, wherein: said third male fastening members formed upon said insulation slab, and said second female fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said insulation slab onto said roof decking member; and said third female fastening members formed upon said insulation slab, and said second male fastening members formed upon said roof decking member have similar geometrical configurations and size dimensions so as to cooperate in said fastening manner so as to fixedly secure said insulation slab onto said roof decking member.
 16. The system as set forth in claim 14, wherein: said first male fastening members formed upon said roofing substructure, and said second female fastening members formed upon said roof decking member, as well as said first female fastening members formed upon said roofing substructure, and said second male fastening members formed upon said roof decking member, have substantially trapezoidal geometrical configurations.
 17. The system as set forth in claim 15, wherein: said third male fastening members formed upon said insulation slab, and said second female fastening members formed upon said roof decking member, as well as said third female fastening members formed upon said insulation slab, and said second male fastening members formed upon said roof decking member, have substantially trapezoidal geometrical configurations.
 18. The system as set forth in claim 14, wherein: said first male fastening members formed upon said roofing substructure, and said second male fastening members formed upon said roof decking member comprise dove tail tenon joint members; and said first female fastening members formed upon said roofing substructure, and said second female fastening members formed upon said roof decking member comprise dove tail mortise joint members, whereby said first and second male tenon, and said first and second female mortise, dove tail joint members together form a dove tail fastening joint.
 19. The system as set forth in claim 15, wherein: said third male fastening members formed upon said insulation slab, and said second male fastening members formed upon said roof decking member comprise dove tail tenon joint members; and said third female fastening members formed upon said insulation slab, and said second female fastening members formed upon said roof decking member comprise dove tail mortise joint members, whereby said second and third male tenon, and said second and third female mortise, dove tail joint members together form a dove tail fastening joint.
 20. The system as set forth in claim 13, wherein: said first male fastening members formed upon said roofing substructure comprise a plurality of transversely spaced, upwardly projecting joist members; said first female fastening members formed upon said roofing substructure comprise spaces defined between adjacent pairs of said plurality of transversely spaced, upwardly projecting joist members of said roofing substructure; said second male fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented downwardly projecting groove members for interfacing in an interdigitated manner with said spaces defined between said adjacent pairs of said plurality of transversely spaced, upwardly projecting joist members of said roofing substructure; and said second female fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented upwardly projecting ridge members for interfacing in an interdigitated manner with said plurality of transversely spaced, upwardly projecting joist members of said roofing substructure.
 21. The system as set forth in claim 13, wherein: said third male fastening members formed upon said insulation slab comprise a plurality of transversely spaced, longitudinally oriented, downwardly projecting ridge members; said third female fastening members formed upon said insulation slab comprise upwardly extending spaces defined between adjacent pairs of said plurality of transversely spaced, longitudinally oriented, downwardly projecting ridge members of said insulation slab; said second male fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented upwardly projecting ridge members for interfacing in an interdigitated manner with said spaces defined between said adjacent pairs of said plurality of transversely spaced, longitudinally oriented downwardly projecting ridge members of said insulation slab; and said second female fastening members formed upon said roof decking member comprise a plurality of transversely spaced, longitudinally oriented, upwardly projecting groove members for interfacing in an interdigitated manner with said plurality of transversely spaced, longitudinally oriented, downwardly projecting ridge members of said insulation slab. 